In semiconductor manufacturing, it is difficult to design and build a semiconductor chip having the same process for a positive channel field effect transistor (pFET) or negative channel field effect transistor (nFET) and the same characteristics in every batch of chips. Varying processes and characteristics of semiconductor chips from chip to chip can affect the performance of the semiconductor chip including the electrical behavior, set-up and hold times, off chip driver slew rate, etc. Sometimes these varying processes and characteristics can be so extreme that the semiconductor chip fails to meet specifications.
A representative pFET or nFET of a semiconductor chip can be tested to determine whether the process for the pFETs and nFETs in the chip are fast (strong) or slow (weak). Based on the test results, action can be taken to offset any undesirable characteristics of the semiconductor chip due to the process. In addition, if an external voltage supplied to the semiconductor chip varies, by determining the variation, action can be taken to adjust for any effects the variation may cause. For example, by evaluating the characteristics of a pFET, nFET, and/or external voltage supplied to the semiconductor chip, an off-chip driver (OCD) on the chip can be adjusted as needed to compensate for any effects due to variations in the characteristics from nominal values.